I downloaded the source code from the website and created the corresponding avd to run the code. Everything compiled and ran just fine but I can't add items to the to-do list. I clicked menu on the stimulator and clicked "Add Item" but then after i typed whatever I wanted to add, nothing happened from there onward. I clicked enter but that only creates a new line of text. I wonder whatI should do to actually add a new to-do item to the list.

click the little pill looking button that is surrounded by the arrows.

Thank you, problem solved for now.
Btw, is it possible to change the key for the input to Enter key though?

Yes its possible. You change the key listener code.

from
to

I changed the code to
if (keyCode == KeyEvent.KEYCODE_DPAD_CENTER || keyCode == KeyEvent.KEYCODE_ENTER)

But then the app quits unexpectedly. Do you know why that happened?